Amex Requirements
Card Identification # 4 digit, non-embossed number printed above your account number on the face of your card. This number is recorded as an additional security precaution.
MasterCard Requirements
Card Identification # 3-digit, non-embossed number printed on the signature panel on the back of the card.. This number is recorded as an additional security precaution.
Discover Requirements
Card Identification # 3-digit, non-embossed number printed on the signature panel on the back of the card.. This number is recorded as an additional security precaution.
Visa Requirements
Card Identification # 3-digit, non-embossed number printed on the signature panel on the back of the card immediately following the Visa card account number. This number is recorded as an additional security precaution.